1 files changed, 57 insertions, 29 deletions

diff --git a/kernel/drivers/media/v4l2-core/v4l2-mem2mem.c b/kernel/drivers/media/v4l2-core/v4l2-mem2mem.c
index 73824a5ad..61d56c940 100644
--- a/kernel/drivers/media/v4l2-core/v4l2-mem2mem.c
+++ b/kernel/drivers/media/v4l2-core/v4l2-mem2mem.c
@@ -17,7 +17,7 @@
 #include <linux/sched.h>
 #include <linux/slab.h>
 
-#include <media/videobuf2-core.h>
+#include <media/videobuf2-v4l2.h>
 #include <media/v4l2-mem2mem.h>
 #include <media/v4l2-dev.h>
 #include <media/v4l2-fh.h>
@@ -357,9 +357,16 @@ int v4l2_m2m_reqbufs(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
 		     struct v4l2_requestbuffers *reqbufs)
 {
 	struct vb2_queue *vq;
+	int ret;
 
 	vq = v4l2_m2m_get_vq(m2m_ctx, reqbufs->type);
-	return vb2_reqbufs(vq, reqbufs);
+	ret = vb2_reqbufs(vq, reqbufs);
+	/* If count == 0, then the owner has released all buffers and he
+	   is no longer owner of the queue. Otherwise we have an owner. */
+	if (ret == 0)
+		vq->owner = reqbufs->count ? file->private_data : NULL;
+
+	return ret;
 }
 EXPORT_SYMBOL_GPL(v4l2_m2m_reqbufs);
 
@@ -427,6 +434,25 @@ int v4l2_m2m_dqbuf(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
 EXPORT_SYMBOL_GPL(v4l2_m2m_dqbuf);
 
 /**
+ * v4l2_m2m_prepare_buf() - prepare a source or destination buffer, depending on
+ * the type
+ */
+int v4l2_m2m_prepare_buf(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
+			 struct v4l2_buffer *buf)
+{
+	struct vb2_queue *vq;
+	int ret;
+
+	vq = v4l2_m2m_get_vq(m2m_ctx, buf->type);
+	ret = vb2_prepare_buf(vq, buf);
+	if (!ret)
+		v4l2_m2m_try_schedule(m2m_ctx);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(v4l2_m2m_prepare_buf);
+
+/**
  * v4l2_m2m_create_bufs() - create a source or destination buffer, depending
  * on the type
  */
@@ -557,24 +583,25 @@ unsigned int v4l2_m2m_poll(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
 		goto end;
 	}
 
-	if (m2m_ctx->m2m_dev->m2m_ops->unlock)
-		m2m_ctx->m2m_dev->m2m_ops->unlock(m2m_ctx->priv);
-	else if (m2m_ctx->q_lock)
-		mutex_unlock(m2m_ctx->q_lock);
-
+	spin_lock_irqsave(&src_q->done_lock, flags);
 	if (list_empty(&src_q->done_list))
 		poll_wait(file, &src_q->done_wq, wait);
-	if (list_empty(&dst_q->done_list))
-		poll_wait(file, &dst_q->done_wq, wait);
+	spin_unlock_irqrestore(&src_q->done_lock, flags);
 
-	if (m2m_ctx->m2m_dev->m2m_ops->lock)
-		m2m_ctx->m2m_dev->m2m_ops->lock(m2m_ctx->priv);
-	else if (m2m_ctx->q_lock) {
-		if (mutex_lock_interruptible(m2m_ctx->q_lock)) {
-			rc |= POLLERR;
-			goto end;
+	spin_lock_irqsave(&dst_q->done_lock, flags);
+	if (list_empty(&dst_q->done_list)) {
+		/*
+		 * If the last buffer was dequeued from the capture queue,
+		 * return immediately. DQBUF will return -EPIPE.
+		 */
+		if (dst_q->last_buffer_dequeued) {
+			spin_unlock_irqrestore(&dst_q->done_lock, flags);
+			return rc | POLLIN | POLLRDNORM;
 		}
+
+		poll_wait(file, &dst_q->done_wq, wait);
 	}
+	spin_unlock_irqrestore(&dst_q->done_lock, flags);
 
 	spin_lock_irqsave(&src_q->done_lock, flags);
 	if (!list_empty(&src_q->done_list))
@@ -739,13 +766,15 @@ EXPORT_SYMBOL_GPL(v4l2_m2m_ctx_release);
  *
  * Call from buf_queue(), videobuf_queue_ops callback.
  */
-void v4l2_m2m_buf_queue(struct v4l2_m2m_ctx *m2m_ctx, struct vb2_buffer *vb)
+void v4l2_m2m_buf_queue(struct v4l2_m2m_ctx *m2m_ctx,
+		struct vb2_v4l2_buffer *vbuf)
 {
-	struct v4l2_m2m_buffer *b = container_of(vb, struct v4l2_m2m_buffer, vb);
+	struct v4l2_m2m_buffer *b = container_of(vbuf,
+				struct v4l2_m2m_buffer, vb);
 	struct v4l2_m2m_queue_ctx *q_ctx;
 	unsigned long flags;
 
-	q_ctx = get_queue_ctx(m2m_ctx, vb->vb2_queue->type);
+	q_ctx = get_queue_ctx(m2m_ctx, vbuf->vb2_buf.vb2_queue->type);
 	if (!q_ctx)
 		return;
 
@@ -803,6 +832,15 @@ int v4l2_m2m_ioctl_dqbuf(struct file *file, void *priv,
 }
 EXPORT_SYMBOL_GPL(v4l2_m2m_ioctl_dqbuf);
 
+int v4l2_m2m_ioctl_prepare_buf(struct file *file, void *priv,
+			       struct v4l2_buffer *buf)
+{
+	struct v4l2_fh *fh = file->private_data;
+
+	return v4l2_m2m_prepare_buf(file, fh->m2m_ctx, buf);
+}
+EXPORT_SYMBOL_GPL(v4l2_m2m_ioctl_prepare_buf);
+
 int v4l2_m2m_ioctl_expbuf(struct file *file, void *priv,
 				struct v4l2_exportbuffer *eb)
 {
@@ -838,18 +876,8 @@ EXPORT_SYMBOL_GPL(v4l2_m2m_ioctl_streamoff);
 int v4l2_m2m_fop_mmap(struct file *file, struct vm_area_struct *vma)
 {
 	struct v4l2_fh *fh = file->private_data;
-	struct v4l2_m2m_ctx *m2m_ctx = fh->m2m_ctx;
-	int ret;
-
-	if (m2m_ctx->q_lock && mutex_lock_interruptible(m2m_ctx->q_lock))
-		return -ERESTARTSYS;
-
-	ret = v4l2_m2m_mmap(file, m2m_ctx, vma);
 
-	if (m2m_ctx->q_lock)
-		mutex_unlock(m2m_ctx->q_lock);
-
-	return ret;
+	return v4l2_m2m_mmap(file, fh->m2m_ctx, vma);
 }
 EXPORT_SYMBOL_GPL(v4l2_m2m_fop_mmap);